1. Field of the Invention
The present invention relates to a device for generating a heavy-ion beam and a method thereof, and more specifically, to a device for generating a heavy-ion beam using a laser beam and a method thereof.
2. Discussion of Related Art
There is a growing interest in laser ion acceleration technology due to its high applicability to basic and applied sciences. Research on application fields such as laser-based proton radiography, fast ion ignition, and cancer treatment is being actively performed.
An ion beam generated by a laser may also be used to generate secondary radiation such as X-rays and a neutron beam.
In order to implement fast carbon ion ignition, a carbon (C6+) ion beam of 450 MeV is necessary. In order to treat cancer, a carbon (C6+) ion beam having an energy of 4-5 GeV and a narrow energy distribution is necessary. In the field of fast ignition or cancer treating devices, a heavy-ion beam having properties of high purity, a narrow energy distribution, and a uniform spatial distribution is necessary.
A device for generating carbon ions using a laser may obtain a carbon ion beam by introducing a high power laser beam into a target.
When the high power laser beam is radiated onto a thin film target, ions in the thin film escape to the outside of the thin film with acceleration energy according to a target normal sheath acceleration (TNSA) model, a radiation pressure acceleration (RPA) model, or the like.
Hydrogen atoms in water molecules adsorbed on a target surface or present within the target as impurities may be accelerated according to the same principle. Hydrogen ions, that is, protons, are lighter than carbon ions and are highly likely to be accelerated before carbon ions under the same conditions. Once protons are accelerated and form a layer, carbon ions that are accelerated thereafter and advance are blocked by the shade of the proton layer and not accelerated above a certain level.
Therefore, in order for carbon ions to have higher acceleration energy, there is a need for a method of disabling proton acceleration.
In the related art, U.S. Pat. No. 6,906,338 discloses acceleration of ions by applying acceleration energy to a target in this manner.